What allergy medications are safe to take while breastfeeding?

FLONASE is SAFEST. According to the aap: sudafed & benedryl are excreted in breast milk but use is compatible with breastfeeding although may cause decreased milk production however these meds can cause lethargy/irritability. The safest meds are the nasal sprays: e.g. Flonase (generic) and others. The newer antihistamines (claritin/zyrtec/allegra) are not well studied but are appear to be safe in short term use.
A couple. The once a day meds like loritadine and fexofenadine have minimal effect on milk production no significant transfer to baby. The nasal rinses/steroid sprays are also worthwhile.